Artificial gem in the nature of asteriae



ug- 17, 1937- R. L. STROTHMAN 2,090,240

ARTIFICIAL GEM IN THE NATURE OF ASTERIAE Filed Feb. 19, 195'! ATTORNEYSPatented Aug. 17, 1937 PATENT OFFICE ARTIFICIAL GEM IN THE NATURE OFASTERIAE Robert L. Strothman, Milwaukee, Wis.

Application February 19, 1937, Serial No. 126,579

6 Claims.

which is relatively inexpensive and commercially practical and which canutilize transparent or translucent substances without any unusualproperties therein, whereby saidasteriae can be produced and sold atrelatively moderate prices. I

In nature, perhaps the finest example of asterism is found in the starsapphire which is that variety of sapphire in which, when the stone iscut and rounded off horizontally with the dome of the crystal, lightstriking the same is condensed across the threelines of crystallineinterference. The three crossed lines produce a star which moves as asource of light, or the star moves in the stone as it is moved relativeto the source of light. The term asterism is applied to any stones whichare cut en cabochon which exhibit distinct stars in refiected light, andany such stones include in general, sapphires, rubies, quartz, andberyls. Natural stones having the quality of asterism are extremely rareand expensive.

In an attempt to imitate the work of nature in the qualities of naturalrare asteriae, there has 0 recently been created a gem with asterism,and such gems have been produced by superimposing asteriated quartzcrystals upon colored backgrounds. These stones so mounted are likewiserelatively expensive because only rare forms of 5 quartz crystals may beused, as the quartz must be asteriated and the mounting of the quartz onthe colored background gives it color and emphasizes the star effectwhen light rays hit the crystal. Obviously, stones produced in themanner last described must be somewhat rare and expensive because allquartz does not have the proper asterism and there is difficulty infinding crystals unmarred by cleavage lines.

With the foregoing in mind, it is therefore a 5 specific object of thepresent invention to provide asteriae wherein the source of the gems isnot limited nor restricted with the result that the same can be producedand mounted in jewelry for relatively reasonable costs.

.0 A further object of the invention is'to provide asteriae wherein thestonesor gems may be produced from many forms of crystalline,transparent or translucent material and may be mounted on backings ofvarious forms of polished ;5 metals.

A further specific object of the invention is to provide artificialasteriae which can be produced in various colors, sizes and shapes, andwhich are especially well suited for use in the artistic,

l0 jewelry and ornamental fields.

These and other objects and advantages of the present invention will beapparent from the following detailed description.

A clear conception of the formation of an improved asteria and of theseveral steps involved in the method of producing the same, may be hadby referring to the drawing accompanying and forming a part of thisspecification in which like reference characters designate the same orsimilar parts in the various views.

Fig. 1 is an enlarged somewhat magnified view of a face of a metallicbacking on which a transparent or translucent stone is to be mounted toproduce an improved asteria;

Fig. 2 is a further magnified or enlarged vicw of a fragment of theshowing in Fig. 1;

Fig. 3 is an enlarged vertical sectional view through a mounted stoneproduced in accordance with the present invention;

Fig. 4 is a plan or top view thereof;

Fig. 5 is a fragmentary detailed sectional view taken on the line 55 ofFig. 3 and on a larger scale; and

Fig. 6 is a view of a completed asteria as mounted in a ring or settingfor jewelry usage.

Referring now more particularly to the drawing, it will appear that abacking for the crystal, gem or stone is indicated by the numeral 8 andsaid backing is of metal with one surface given a mirror-like finish.Any of the following metals may be used for this purpose, namely;silver, copper, brass, Monel metal, and stainless steel, and the backingis of course cut to the desired size and configuration so as to fit thebase of the stone or crystal to be superimposed thereon.

The formation of the face of the backing to which the stone or crystalis to be applied, is extremely important in the attainment of thepresent invention.

As will appear most clearly from Figs. 1 and 2, the ultimate upper face'of the backing has scratched, engraved or cut therein, over its entiresurface, three sets of lines or grooves, with the lines of each setextending across and angulariy relative to the lines of the othersets.As shown most clearly in Fig. 2, one set of the lines or scratches aredesignated by the numerals 9 and the lines of this set are all paralleland spaced apart slightly. These lines 9 are traversed at an angle byanother set of spaced and parallel lines i0. and the sets of lines 9 andill are both traversed or intersected by a set of parallel and spacedapart lines or grooves ii.

In actual practice, the various lines or scratches 9, l0 and il may bemade in the face of the metal backing, by the use of emery orcarborundum paper. The emery or carborundum paper may be rubbed on thebacking in one direction to produce one desired set of lines, then -itmay be rubbed over the backing in another direction to produce a secondset of lines, and finally it is rubbed in still another or thirddirection to produce a final set of lines or scratches. The fineness orcoarseness of the emery paper used, determines the fineness orcoarseness of the lines or scratches, and this is dependent upon thesize and type of stone to be mounted on the backing. Small stonesrequire the formation of fine lines or scratches on the backing, whereaslarge stones require the production of deeper or coarser lines orscratches on the backing which are accomplished by coarser emery paper.A sleepy effect in the finally produced stone can be obtained by alesser degree of polishing imparted to the upper face of the backing 8.

The stone to be mounted on the backing must be cut en cabochon either inround or oval contour, or in slight variations thereof. stone, quartz,sapphire, ruby, glass, or any other similar transparent or translucentmaterial may be used, and the color of the same is immaterial. Incutting the stone en cabochon, care must be taken not to have it domedtoo high, otherwise the rays ultimately reflected will not appear on thesurface of the stone but will appear too far below the surface of thestone.

After the selected stone has been cut and shaped, it is ready to bemounted on the upper surface of the backing 8, and as shown in thedrawing, the stone thusprepared is indicated by the numeral l2. Thesecurement of the fiat face of the stone to the backing can beaccomplished by cementing the same together by the use of any waterprooftransparent cementitious material as at l3. Under certain conditions, ifother forms of securement are utilized, the adjacent faces of the stoneand backing may be protected with a coating of banana oil, and thecementing can be dispensed with.

For use in the jewelry or ornamental field, the backed stone may then bemounted in a suitable setting, and as shown in Fig.6, it forms theornamental portion of a ring ll. When the improved stone is mounted on abacking in the manner described, it will be found that it has thequality of asterism and when held in line with a light source, asix-sided star will be reflected therein which moves in or over thestone as the stone or light source are moved relative to one another. Ithas been found that in the present invention, this phenomena is producedby virtue of the rays of light from the light source striking the seriesof parallel lines 9, l0 and II on the base and being reflected throughthe stone I! to the observer. Each of the lines causes a small point oflight to be reflected. With the lines arranged on the backing asdescribed, and covered by the transparent or translucent stone, thethree sets of lines produce three sets of rays or a six-pointed star.The sets of rays are indicated by the broken line showings in Figs. 3and 4, and it will be noted that the lines of rays are at ninety degreeangles relative to the respective sets of lines on the backing, and theeffect of the star in the final product is shown in Fig. 6.

From the foregoing description of the mode of producing an improvedasteria, it will be apparent that the present invention provides anextremely simple, inexpensive and effective method of manufacturinghighly attractive ornamental stones or gems for jewelry usage. Theasteriae thus produced, very closely approach in For the to limit thepresent invention to the precise details of construction herein shownand described, for various modifications or variations within the scopeof the appended claims, may occur to persons skilled in the art.

What is claimed as the invention is:

1. An asteria, comprising a gem normally devoid of asterism and having abase portion, and a plate on which the base portion is secured andhaving light reflecting qualities, one of the adjoining faces of theplate and gem having series of lines therein to produce asterism in thegem when light from a source is reflected through the gem by the plate.I

2. An artificial asteria, comprising a light transmitting stone normallydevoid of asterism and having a base face, and a reflector plate onwhich said base face is mounted, one of the adjoining faces of the stoneand plate having series of intersecting lineations therein whereby, whenlight froma source strikes said plate it will be reflected into thestone in condensedintersecting rays to produce asterism in the stone.

3. An artificial asteria, comprising a light transmitting, colored stonenormally devoid of asterism andhaving a flat base face, a reflectorplate on which said base face is mounted, one of the adjoining faces ofthe stone and plate having two seriesof intersecting lineations thereon,the lineations of one series intersecting those of the other serieswhereby, when light from a source strikes said plate and lineations itwill be reflected into the stone in condensed intersecting rays toproduce asterismin the stone.

4. An artificial asteria, comprising a domeshaped, light transmittingstone normally devoid of asterism and having a flat base face, and areflector plate on which said base face is mounted, the adjacent face ofthe reflector plate having a plurality of lines therein whereby whenlight from a source strikes said plate it will be reflected into thestone to produce asterism therein.

5. An artificial asteria, comprising a domeshaped, light transmittingstone normally devoid of asterism and having a flat base face, and areflector plate on which said base face is mounted,

the adjacent face of the reflector plate having three series of finelines thereon, the lines of each series being intersected by the linesof both of the other series whereby when light from a source strikessaid plate and the lines it will be reflected into the stone incondensed intersecting rays to produce asterism in the stone.

6. An artificial asteria, comprising a domeshaped, light transmitting,colored stone normally devoid of asterism and having a-fiat base face,and a reflector plate on which said base face is mounted, the adjacentface of the reflector plate having three series of closely-adjacent,fine lines therein, the lines of each series being in parallelism andbeing intersected by the lines of both of the other series whereby whenlight from a source strikes said'plate and the lines it will bereflected into the stone in condensed intersecting rays to produceasterism in the stone.

ROBERT L. STROTHMAN.

